Telephone hook-switch and cut-out.



J. T. GRAY.

TELEPHONE HOOK SWITCH AND CUT-OUT.

APPLICATION FILED MAIL-4. 9l6.

1 ,Q694Q5. Patented June 11, 1918.

1 wimz m /a affozncq JOHN T. GRAY, OF GREAT FALLS, MONTANA.

TELEPHONE HOOK-SWITCH AND CUT-OUT.

incense.

Specification of Letters Patent.

Patented June 11, 1918.

Application filed March 4, 1916. Serial No. 82,172.

To all whom it may concern:

Be it known that 1, JOHN T. GRAY, a citizen of the United States,residing at Great Falls, in the county of Cascade and State of Montana,have invented certain new and useful Improvements in TelephoneHook-Switches and Cut-Outs, of which the following is a specification.

The present invention relates to telephony and more particularly to newand useful improvements in hook operated switches for use in protectingtelephone systems.

An object of my invention is to provide in combination with the usualsub-station circuits a cut-out whereby all of the talking circuits andthe generator circuit are completely isolated from the line when thetelephone is not in use, whereby to prevent injury of the telephonecircuits by lightning or other electrical surges.

Another object of my invention is to provide an improved cut-out of theclass described which is combined with the usual hook switch and adaptedto be opened when the receiver is on the hook.

A further object of my invention is to provide a modified form of switchfor use in connection with a bridging set, whereby to cut in the bellcircuit when the talking circuit is open and to cut out the bell circuitwhen the talking circuit is closed.

A still further object of my invention is to provide in a simple andcompact structure a durable switch for cooperation with the hook of theusual telephone set and to provide a switch of this character whichopens a sufficient distance to prevent ordinary electrical surges fromreaching the talking circuits.

It will be understood that the circuits in which this device isinstalled do not form any part of my invention and have, therefore, beenomitted from the showing,

Other objects and advantages will appear from the following detaildescription and the claim, taken with an inspection of the accompanyingdrawings, in which Figure 1 is a side elevation of my improved cut-outshowing the same applied in combination with the usual hook switch,

Fig. 2 is a bottom plan view of the same,

Fig. 3 is a side elevational view of a modified form of the switch.

Referring more particularly to the drawings, wherein similar charactersof reference designate like and corresponding parts throughout thevarious views, 1 designates a casing in which is mounted the usualtelephone set, the usual telephone hook 2 being mounted in the bracket 3and having the hook portion 4: on the outer end thereof. The usual hookswitch is provided, con trolled by the hook 2, and comprises theresilient strips 5, 6 and 7 mounted on an insulating support 8. Thestructure of the hook switch is of the usual kind and need not befurther dwelt upon at this time.

My improved cut-out broadly comprises a swltch, having a structurehereinafter set forth in detail, interposed in the main leads from theline to the talking circuits and 0perable to open said circuits when thereceiver is on the hook and the latter is in depressed position. As bestshown in Figs. 1 and 2 my improved cut-out is designated S in itsentirety and comprises conductor arms 9 pivoted at 10 in brackets 11,said brackets being connected to the generator circuit of the phone.Jumpers 12 connected to the arms 9 and brackets 11, respectively, serveto con duct current around the pivots 10 and revent any electricaldisturbances cause by poor contact at these points. The arms 9 areconnected to move together by means of a transverse bar 13 of insulatingmaterial having a yoke 14: removably secured thereto by means of screws15, said yoke having an opening therein through which the arm 2 of thereceiver hook passes. Thus it will be seen that when the telephone hookis depressed the main switch S comprising the arms 9 will be opened.

Of course the bearing brackets 11 are mounted on a suitable base 16 ofporcelain or the like. The leading-in wires from the main line areconnected to stationary terminals 17 which are adapted to be engaged bythe arms 9, spring strips 18 permanently connected as at 19 to said armsserving to insure true contact. Of course, platinum contacts (not shown)may be employed at the points at which the spring strips 18 engage theterminals 17, but these are modifications that may be made in reducingthe device to actual practice.

It will be seen that when the hook 2 is depressed by virtue of thereceiver being placed thereon the switch S will be opened, and saidswitch being interposed in the talking circuits the circuits will be outout from the main line. It is preferable that considerable distanceexist between the switch arms 9 and the terminals 17 when the switch isopen in order to insure the talking circuits against injury.

Thus it will be seen that when the receiver is placed upon the hook 2,the arms 9 carrying the spring strips 18 will be caused to move awayfrom the terminal 17 Which opens the talking circuit.

Referring to the Fig. 3, an extension 43 is provided in one of the arms9, said extension having an enlargement 44- on the free end thereofengageable with a spring contact member 45 mounted at 46 on the base 1.The spring contact arm 45 is connected to the bell circuit so that whenthe talking circuits are open the bell circuit is automatically closed.The sub-station circuits employed in connection with my improvedtelephone protector are practically identical with the circuits now incommon use.

What I claim as new and desire to secure by Letters-Patent is In atelephone cut-out, the combination with a hook switch, of a main switchincluding a pair of interconnected pivoted parallel conductor arms, ayoke carried by the arms engaged in said hook switch, spaced rigidcontact posts, and spring strips carried by the conductor arms forengaging said contact posts.

In testimony whereof I atfix my signature hereto.

JOHN T. GRAY.

melee of this patent may be attained for five cents each, by addressingthe "Commissioner of Patents,

Washington, D. 0.

